Machine for trimming sheet material



Dec. 28, 1965 o. GREINER 3,225,638

MACHINE FOR TRIMMING SHEET MATERIAL Filed April 8, 1964 ll il I k n I H u I K/ A/ a) 4 aw H hm MN /2 5 a United States Patent 0 MACHINE FGR TRTMMENG SHEET MATERIAL Otto Greiner, Simter Strasse, Erlenbrunn, near Pirmasens, Germany Filed Apr. 3, 1964, Ser. No. $525,396

Claims priority, appiication Germany, Apr. 9, 1963,

M 44,394 3 tjiaims. (5. 83-65%) This invention is concerned with the trimming of sheet or slab material on the movable table of a punching press, particularly a bridge beam type or truck beam type punching press.

For the punching of cut-out shapes from a stack of trimmed sheets or slabs of material, for example, sheets of paper, it is known, particularly if the portions to be punched out are close together, to secure the work, that is, the stack of material by means of a frame against shifting during the punching process. As these known frames are fnted stationary on the press table, the punch knife in these punching presses, which are, as a rule, automatic, always hits the same places on the punch base, which is thereby prematurely worn out, since it is always located in the same position underneath the frame.

The object of this invention is to provide a novel construction of a punch table for a bridge beam type or truck beam type punching press, having a punch base and a work holding frame for the material to be punched, which leads to a longer term of utility of the punch base.

Another object of the invention is the provision in such a press of a punch table having a punch base and a non-slidable frame for the material to be punched, the same frame, which is capable of being raised being carried on the table top and the punch base being located slidably between the table top and the under-side of the frame.

Thus the punch base can be slid about on the table top in relation to the frame, so that the punch knives, although maintained in alignment in respect of the table top and the frame, can be made to bear on varying areas of the punch base by reason of the displacement of said punch base.

One embodiment of the invention is shown, by way of example, in the accompanying drawings, wherein: FIG. 1 is a plan view of the press table top, the frame and the punch base,

FIG. 2 is a longitudinal section along line 1-1 of 3,ZZ5,%38 Patented Dec. 23, 1955 FIG. 1, showing the punch base displaced relatively to said table and said frame, and

FIG. 3 is a view similar to FIG. 2, showing the punch base in alignment with the frame.

In the embodiment illustrated the movable table 1 of a conventional punch press (other parts of which are not shown in the drawin s), has two guide bolts 2, extending upwardly from its working surface, which engage in holes in end flanges of a holding frame 3, thereby securing same against sliding on the table top 1, but permitting a raising of the frame along the guide bolts 2. The bolts 2 may be replaced by slat guides or similar means.

On the table top l and under the frame 3 is slidably arranged a punch base 4, which is larger than the guiding cut-out, that is, the main opening of the frame 3, which receives the material to be punched. The holding bolts 2 are sufficiently long to allow of the insertion of punch bases 4 of different heights, Without the frame 3 being deprived of guidance.

It is possible, however, to shift the punch base 4 in respect of the frame 3, and to make better use of the base in this way, and also a aim to utilise worn bases without regard to thickness.

I claim:

1. In combination with the table of a punching press having upstanding guide elements, a punching guide frame for the material to be punched, and a punch base interposed between said table and said frame which latter has portions coacting with said guide elements whereby said frame is precluded from sliding over the table top, but capable of being raised relatively to said table top, to permit of adjustment of said punch base by sliding between said table top and said frame.

The combination as claimed in claim 1, wherein said table guide elements are bolts adapted for sliding engagement in flanges of said frame.

3. The combination as claimed in claim 1, wherein said punch base is substantially larger than the punch guiding opening of said frame.

References Qited by the Examiner UNITED STATES PATENTS 398,341 2/1889 Morgan 83532 2,467,546 4/1949 Anderson 8354l ANDREW R. JUHASZ, Primary Examiner. 

1. IN COMBINATION WITH THE TABLE OF A PUNCHING PRESS HAVING UPSTANDING GUIDE ELEMENTS, A PUNCHING GUIDE FRAME FOR THE MATERIAL TO BE PUNCHED, AND A PUNCH BASE INTERPOSED BETWEEN SAID TABLE AND SAID FRAME WHICH LATTER HAS PORTIONS COACTING WITH SAID GUIDE ELEMENTS WHEREBY SAID FRAME IS PRECLUDED FROM SLIDING OVER THE TABLE TOP, BUT CAPABLE OF BEING RAISED RELATIVELY TO SAID TABLE TOP, TO PERMIT OF ADJUSTMENT OF SAID PUNCH BASE BY SLIDING BETWEEN SAID TABLE TOP AND SAID FRAME. 